Trace element analysis of L and LL chondrites: Comparison of Antarctic and non-Antarctic meteorite populations

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6935839

Kaczaral, P W

The author reports compositional data for mobile/volatile trace elements Au, Co, Se, Ga, Rb, Cs, Te, Bi, In, Ag, Zn, Tl and Cd in Antarctic L chondrites and both Antarctic and non-Antarctic LL chondrites. A comparison of previously obtained non-Antarctic L chondrite data to L chondrite results obtained in this work indicates that significant reason exists to doubt that the two meteorite populations derived from the same parent source. Of the 13 trace elements examined, 7 showed statistically significant differences between mildly-shocked populations; the Antarctic collection had the lower mean elemental concentration in each of those 7 cases. Two-element plots and correlation profiles also indicated significant differences between Antarctic and non-Antarctic populations. Shock-induced trace element mobilization, a major determinant of trace element contents in non-Antarctic L chondrites, plays a minor role in determining elemental abundances in Antarctic L chondrites. After ruling out alternate explanations, the author believes these differences to have a preterrestrial origin and attribute them to a changing meteorite flux with time. Due to a lack of available samples, the LL chondrite study was inconclusive. The data are consistent with previous findings which suggest Yamato Mts. and Victoria Land samples may be compositionally different. A positive correlation between trace element content and petrologic type was observed in LL chondrites. Whether this unexpected finding is due to a unique shock history of LL4 + 5 chondrites or some other explanation is unclear; more samples must be analyzed and shock facies must be obtained to further investigate this finding. Shock-induced trace element mobilization was found to be a minor factor in determining trace element content in LL chondrites.

• Research Organization: Purdue Univ., Lafayette, IN (USA)
• OSTI ID: 6935839
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ALKALI METALS
ANTARCTIC REGIONS
ANTARCTICA
BISMUTH
CADMIUM
CESIUM
CHEMICAL ANALYSIS
CHONDRITES
COBALT
COMPARATIVE EVALUATIONS
ELEMENTS
GALLIUM
GOLD
IMPACT SHOCK
INDIUM
MATTER
METALS
METEORITES
MULTI-ELEMENT ANALYSIS
POLAR REGIONS
RUBIDIUM
SELENIUM
SEMIMETALS
SILVER
STONE METEORITES
TELLURIUM
THALLIUM
TRACE AMOUNTS
TRANSITION ELEMENTS
VARIATIONS
VOLATILE MATTER
ZINC